1. 16 Dec, 2015 1 commit
    • quchen's avatar
      Add `-W(no-)xxx` aliases for `-f(no-)warn-xxx` flags · 2206fa8c
      quchen authored
      This also updates the user's guide to refer to the `-W`-based warning
      flags by default.
      
      Quoting the release note entry:
      
      | Warnings can now be controlled with `-W(no-)...` flags in addition to
      | the old `-f(no-)warn...` ones. This was done as the first part of a
      | rewrite of the warning system to provide better control over warnings,
      | better warning messages, and more common syntax compared to other
      | compilers. The old `-fwarn...`-based warning flags will remain
      | functional for the forseeable future.
      
      This is part of
      https://ghc.haskell.org/wiki/Design/Warnings
      and addresses #11218
      
      Reviewed By: hvr, bgamari
      
      Differential Revision: https://phabricator.haskell.org/D1613
      2206fa8c
  2. 11 Dec, 2015 1 commit
    • eir@cis.upenn.edu's avatar
      Add kind equalities to GHC. · 67465497
      eir@cis.upenn.edu authored
      This implements the ideas originally put forward in
      "System FC with Explicit Kind Equality" (ICFP'13).
      
      There are several noteworthy changes with this patch:
       * We now have casts in types. These change the kind
         of a type. See new constructor `CastTy`.
      
       * All types and all constructors can be promoted.
         This includes GADT constructors. GADT pattern matches
         take place in type family equations. In Core,
         types can now be applied to coercions via the
         `CoercionTy` constructor.
      
       * Coercions can now be heterogeneous, relating types
         of different kinds. A coercion proving `t1 :: k1 ~ t2 :: k2`
         proves both that `t1` and `t2` are the same and also that
         `k1` and `k2` are the same.
      
       * The `Coercion` type has been significantly enhanced.
         The documentation in `docs/core-spec/core-spec.pdf` reflects
         the new reality.
      
       * The type of `*` is now `*`. No more `BOX`.
      
       * Users can write explicit kind variables in their code,
         anywhere they can write type variables. For backward compatibility,
         automatic inference of kind-variable binding is still permitted.
      
       * The new extension `TypeInType` turns on the new user-facing
         features.
      
       * Type families and synonyms are now promoted to kinds. This causes
         trouble with parsing `*`, leading to the somewhat awkward new
         `HsAppsTy` constructor for `HsType`. This is dispatched with in
         the renamer, where the kind `*` can be told apart from a
         type-level multiplication operator. Without `-XTypeInType` the
         old behavior persists. With `-XTypeInType`, you need to import
         `Data.Kind` to get `*`, also known as `Type`.
      
       * The kind-checking algorithms in TcHsType have been significantly
         rewritten to allow for enhanced kinds.
      
       * The new features are still quite experimental and may be in flux.
      
       * TODO: Several open tickets: #11195, #11196, #11197, #11198, #11203.
      
       * TODO: Update user manual.
      
      Tickets addressed: #9017, #9173, #7961, #10524, #8566, #11142.
      Updates Haddock submodule.
      67465497
  3. 03 Oct, 2015 1 commit